20 research outputs found
Identification of the
The α-decay chain 109Xe â 105Te â 101Sn was identified at the Holifield Radioactive Ion Beam Facility. Advances in digital electronics have made possible the identification of both alpha emitters in the same experiment despite the disparate half-lives of 13 ±2âms and 620 ±70âns for 109Xe and 105Te, respectively. Two α-decay transitions were observed from 109Xe with Qα values of 4067 ±10 and 4217 ±8âkeV. One transition between the ground states of 105Te and 101Sn was observed with a Qα value of 4889 ±6âkeV. Using the measured half-lives, branching ratios, and Qα values the reduced α-decay widths, ÎŽ2, were determined. Comparison of the ÎŽ2 value for 105Te with 213Po indicates a âsuperallowed" character in the α emission of 105Te
Spectroscopy of transfermium nuclei using the GABRIELA set up at the focal plane of the VASSILISSA recoil separator
International audienceAn IN2P3âJINR collaboration has launched a project called GABRIELA at the Flerov Laboratory for Nuclear Reactions (FLNR) within the Joint Institute for Nuclear Research (JINR) in Dubna (Russia). The goal of the project is to perform gammaâray and internal conversion electron spectroscopy of heavy nuclei produced in fusionâevaporation reactions and transported to the focal plane of the recoil separator VASSILISSA. During five experimental campaigns of GABRIELA, the detection system has gained in sensitivity and new spectroscopic information has been obtained for 249Fm, 251Fm, 253No and 255Lr. In this contribution new results for 253No will be discussed. © 2010 American Institute of Physic
Spectroscopy of Transfermium Nuclei Using the GABRIELA Setup
International audienceHeavy elements above Fm (Z = 100) are nuclei with vanishing liquid-drop fission barriers and are therefore entirely stabilized by quantum shell effects. Due to the large density of single-particle levels and strong polarized Coulomb fields, theoretical predictions of magic numbers are extremely model dependent. Furthermore, shell closures for one nucleon species depend strongly on the number of the other species. Reliable experimental data is needed in order to test and constrain theory. As there is a lack of such data in the region, new data is needed along with the confirmation of previous data. A detection system dedicated to the spectroscopy of transfermium nuclei was constructed in 2004 and installed at the focal plane of the VASSILISSA separator at the FLNR, Dubna, by a Franco-Russian collaboration. The results from the 2009 campaign will be presented